LIFE HISTORY OF A FERN 



149 



Fig. 107. — Portion of the rhizome of the common brake (Pieris aquilina) 

 showing a cross-Bection view at the right. The two dark areas are scler- 

 euchyma. 



Fig. 108. — Cross-section of the rhizome of the bracken fern {Pteris aqui- 

 lina), showing the tissue systems. Greatly magnified. 



